1. Field of the Invention
The present invention relates to a hybrid integrated circuit device, and more particularly to a light irradiation device in which a plurality of light emitting elements are mounted.
2. Description of the Related Art
When an article is to be irradiated with a large amount of light, a device such as an electric lamp is usually used. In some cases, in order to reduce the size and weight of the device and the power consumption, a device in which light emitting elements 2 are mounted on a printed circuit board 1 as shown in FIG. 6 is used.
As the light emitting elements, light emitting diodes which are configured by semiconductor materials are mainly used. Alternatively, semiconductor lasers or the like may be used.
In each of the light emitting diodes 2, two leads 3 and 4 are used. The rear face (anode or cathode) of a light emitting diode chip 5 is fixed to the one lead 3 by soldering or the like. The other lead 4 is electrically connected via a thin metal wire 6 to an electrode (cathode or anode) on the surface of the chip. A transparent resin sealing member 7 which will serve as a lens is formed to seal the leads 3 and 4, the chip 5, and the thin metal wire 6.
On the other hand, electrodes 8 and 9 for supplying a power to the light emitting diode 2 are disposed on the printed circuit board 1. The leads are inserted into through holes opened in the electrodes. The light emitting diode 2 is mounted on the board via solder or the like.
A light irradiation device using such light emitting diodes is described in, for example, JP-A-9-252651.
As described above, the light emitting element 2 is configured by a package into which the resin sealing member 7, the leads 3 and 4, and the like are incorporated. When a large number of light emitting elements are mounted, therefore, there arise problems such as that the circuit board 1 is large in size and weight. Since the heat radiation properties of the circuit board itself are inferior, the circuit board has a problem in that the temperature of the whole device is excessively raised. Consequently, the temperatures of semiconductor chips themselves which constitute the light emitting elements are raised, thereby producing a problem in that the driving ability is lowered.
In the light emitting diode 2, light is emitted also from side and rear faces, and hence light directed toward the circuit board 1 exists. Since the circuit board 1 is configured by a printed circuit board, there is another problem in that irradiation of a high efficiency cannot be realized.
The invention has been conducted in view of the above-discussed problems. In the invention, the surface of a conductive pattern constituting a protection circuit for a light emitting diode is made of a metal material which is excellent in light reflection, whereby the efficiency of reflection with respect to light emitted from the light emitting diode can be improved.
Furthermore, an island-like conductive pattern is disposed in an open region surrounded by a conductive pattern and/or a semiconductor element, the conductive pattern and/or the semiconductor element constituting the protection circuit, and the surface of the conductive pattern is made of a metal material which is excellent in light reflection, whereby the efficiency of reflection with respect to light emitted from the light emitting diode can be improved.
When the semiconductor element constituting the protection circuit is to be die-bonded or wire-bonded, a bonder knows the position of a mark and then performs an alignment operation. Also the surface of the mark is made of a metal material which is excellent in light reflection, whereby improvement of the reflection efficiency can be realized.
In order to prevent the semiconductor element from being deteriorated, a resin is applied to the semiconductor element. The applied resin is cured. An uncured resin is fluid and hence may flow even to an unexpected place. In such a case, there arise problems as follows. When a resin flows to a chip resistor and is then cured, the resistance is varied. When a resin flows onto wiring and is then cured, the wiring is peeled off. A pattern for preventing such a flow from occurring is disposed in an open region. Therefore, the efficiency of reflection with respect to light emitted from the light emitting diode can be improved by configuring the surface of the pattern with a metal material which is excellent in light reflection.
Each aspect of the device described below is separately illustrative of the various embodiments of the invention and is not intended to be restrictive of the broad invention.
A first aspect of the device is a hybrid integrated circuit device which comprises:a wiring portion consisting of a first wiring of reflective conductive film so as to cover an whole surface of a substrate; and a second wiring facing to the first wiring through a slit; a light emitting element mounting region formed on a part of the wiring portion so that a light emitting element is mounted; and
a light emitting element mounted on the light emitting element mounting region.
A second aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the slit has a constant width for a whole area.
A third aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the reflective conductive film is formed so as to guide a light emitted by the light emitting element mounted on the light emitting element mounting region into a front direction effectively.
A fourth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the wiring portion is covered with a reflective conductive film in a whole region except for a slit for isolating the first wiring and the second wiring each other.
A fifth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the slit has a smallest width which is able to be isolated.
A sixth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein said hybrid integrated circuit device comprises: a first wiring disposed on a hybrid integrated circuit substrate; a second wiring which is disposed in opposed relation with said first wiring; and a plurality of light emitting diodes which are connected in series between said first and second wirings,
a protection circuit for said light emitting diodes is mounted in a region of said hybrid integrated circuit substrate, and a surface of a conductive pattern constituting said protection circuit is configured by a light reflective film.
A seventh aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein said hybrid integrated circuit device comprises: a first wiring disposed on a hybrid integrated circuit substrate; a second wiring which is disposed in opposed relation with said first wiring; and a plurality of light emitting diodes which are connected in series between said first and second wirings,
a protection circuit for said light emitting diodes is mounted in an region of said hybrid integrated circuit substrate, an island-like conductive pattern is disposed in an open region surrounded by a conductive pattern and/or a semiconductor element, said conductive pattern and/or said semiconductor element constituting said protection circuit, and a surface of said island-like conductive pattern is configured by a light reflective film.
An eighth aspect of the device is a hybrid integrated circuit device according to the sixth aspect, wherein said island-like conductive pattern is an alignment mark.
An eighth aspect of the device is a hybrid integrated circuit device according to the sixth aspect, wherein said island-like conductive pattern is used for stopping a flow of a resin.
A tenth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein said hybrid integrated circuit device comprises: a first wiring which is disposed on a metal substrate with being insulated from said metal substrate; a second wiring which is disposed in opposed relation with said first wiring; a plurality of electrodes which are disposed between said first and second wirings; and a plurality of light emitting diodes which are connected between said first wiring and said electrodes, between said electrodes, and between said electrodes and said second wiring to be connected in series between said first and second wirings,
a protection circuit for said light emitting diodes is mounted in an region of said metal substrate, an islandlike conductive pattern is disposed in an open region surrounded by a conductive pattern and/or a semiconductor element, said conductive pattern and/or said semiconductor element constituting said protection circuit, and
surfaces of said first electrode, said electrodes, said second wiring, and said island-like conductive pattern are configured by a light reflective film.
An eleventh aspect of the device is a hybrid integrated circuit device according to the tenth aspect, wherein said film is a film which is formed on a conductive pattern made of copper, and which is made of anyone of Au, Ni, and solder.
A twelfth aspect of the device is a hybrid integrated circuit device according to the tenth aspect, wherein a resin which seals said semiconductor element constituting said protection circuit is disposed on said semiconductor element, and said resin is contacted with said island-like conductive pattern.
A thirteenth aspect of the device is a hybrid integrated circuit device according to the tenth aspect, wherein the substrate is made of a surface insulated metal substrate.
A fourteenth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the first and second wiring are disposed on the substrate so as to be symmetric each other with respect to the centerline of the substrate.
A fifteenth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the light emitting element is a plurality of light emitting diodes which are mounted on the first wiring and the second wiring so as to be odd raw in a direction perpendicular to the first and second wirings.
A sixteenth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the first wiring and the second wiring are extended to the both side ends of the substrate.
A seventeenth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the substrate is made of a plurality of metal substrates whose surfaces are covered with an insulating film, and each of the substrates has a first wiring formed along a first side of the metal substrate; a second wiring formed along a second side opposite to the first side; and each of light emitting diodes connected on the first and second wirings which are connected over a distance between first and second substrate so that the light emitting diodes connected in serial by means of metallic wiring.
An eighteenth aspect of the device is a hybrid integrated circuit device according to the first aspect, wherein the first substrate and the second substrate which are juxtaposed each other, have opposite wiring pattern each other so that the first wirings of the first and second substrates can be connected at a nearest neighbor point.
An nineteenth aspect of the device is a hybrid integrated circuit device according to the eighteenth aspect, wherein the first and second wiring are formed on the substrate so as to be symmetric each other with respect to a center line of the substrate, and bonding area or solder bonding area is formed on each of both ends of the substrate.
A twentieth aspect of the device is a hybrid integrated circuit device according to the nineteenth aspect, wherein the bonding area or solder bonding area has a plurality of areas formed on each of both ends of the substrate.
A twenty first of the apparatus is a light emitting apparatus using a hybrid integrated circuit device according to the fifth aspect, wherein the device is formed so as to use a water having been cooled the substrate as a water for feeding a plant substrate, and a light generated by the device is irradiated to the plant to be grown owing to a light synthetics by the diodes mounted on the substrate.
As seen from the above description, when a substrate mainly made of Al is employed, particularly, it is possible to realize a hybrid integrated circuit device which can attain excellent heat radiation properties, light weight, and high workability, and which has a high reflection efficiency.